Rear wheel bearing

Hi everyone. I've just changed a rear wheel bearing on my wifes 2011 K13 but have had to fit the new hub nut without knowing the torque setting. There appears not to be a Haynes manual for this car and little else on the internet. It seems a very small nut for a hub nut. Would anyone know the torque settings for this car in general please? The other rear wheel is now beginning to 'whine'. Thank you, Ant.
 
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